21288655688212 has 24 divisors (see below), whose sum is σ = 41953010625792. Its totient is φ = 9364511299200.

The previous prime is 21288655688173. The next prime is 21288655688249.

21288655688212 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21288655688212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7803758053 + ... + 7803760780.

It is an arithmetic number, because the mean of its divisors is an integer number (1748042109408).

Almost surely, 2^{21288655688212} is an apocalyptic number.

21288655688212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21288655688212 is a deficient number, since it is larger than the sum of its proper divisors (20664354937580).

21288655688212 is a wasteful number, since it uses less digits than its factorization.

21288655688212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15607518879 (or 15607518877 counting only the distinct ones).

The product of its digits is 58982400, while the sum is 64.

The spelling of 21288655688212 in words is "twenty-one trillion, two hundred eighty-eight billion, six hundred fifty-five million, six hundred eighty-eight thousand, two hundred twelve".